Igniting-furnace for pulverous fuel.



N K. H. EKELUND. IGNITING FURNACE FOR PULVEROUS FUEL.

APYLIUATION FILED SEPT. 12, 1907.

Patented June '7, 1910.

' N ILs KAR ERMAN i'zxniliinnpor Jame-ems, swnnniv.

' mamma resaaes i onrnnvnao us iUlsilff-S .T '0 all whom it may concern;

- Be it known that 1,, NiLs IiKRTf'HERMAN EKnnUNn, a subject of the King of Sweden, and resident of ()stra Storgata1r13, Jonkoping, in the Kingdom of Sweden, have invented certain new and useful Improve- -ments in Igniting-Furnaces for Pulverous Fuel, of which the following is a specification, reference being hadtherei n to the accompanying drawing.

There is no doubt that the pulverous form is the most convenient one for solid fuel, by' reason of the fact that the said form affords the opportunity of a combustion under the most favorable conditions. Experience has,

however, provedthat certain practical dithculties are to be overcome if one shall be able to utilize the theoretical possibilities which are involved when firing with pulverous fuel.

The principal condition for reaching a good result is of course to have a perfectly suitable fuel which is inflammable and easily combustible, but certain measures are also required, especially as to the ignition. There are, even in the best fuel, certain particles,

. which ignite with difiiculty and some grains have a tendency to fall down unburned. This fact has hitherto been too little considered, and, therefore, the difiiculties attached to the above method of firing have notbeen overcome.

The present invention has for its object an igniting-furnace which admits of a perfectly rational firing with pulverous fuel.

Referring to the accompanying drawing, Figure l is a vertical section through a furnace according to the present invention, and

Fig; 2 is a horizontal section through the same on line 22 of Fig. 1.

The furnace consists of a box 1 supported on wheels 2, the sides of the said box being held together by means of iron rods 3. The

' box is divided into three compartments, viz.

the mixing compartment 4:, the igniting compartment 5 and the fire-place 6. The mixing compartment consists of a tube which is attached to the exterior end of the box and is inwardly-provided with screw-like screens 7. A tube 8,coming from apressure-fan or similardevice, supplying air and pulverous fuel, opens into the tube 4; from out side. The igniting compartment 5 consists of a tube wider than the tube 4 and provided .with an internal casing of fireproof material.v

The tube 5 issuitably alined with the tube 4 but is located at some distance from the p ms we e -T J Patented, Junei, 1910'.

' Application filedseptem'ber 12, 1907. Serial No. 392,605.

latter so'that there is an intermediatespace between the two adpwent ends of thetubes.

The tube 5 extendssome distance out' of the box and is surrounded by a gasket 11, '60 4 An air-supplying tube 9, having'a forwardly inclined position, is inserted into the tube 5.

The fire-place 6 which is .in the ordinary manner provided with grate anddoor, is

located under the tube 4 and its fire channel v 10 consists of the above mentioned inter- .mediate space between thetubes 4 and 5.' I a The inclined bottom 12 of the channel 10 forms at the same time the' fire-bridge 0f the fire-place 6. The tube 5 forms a com- 7 mon outlet for the compartment fand'f the.

fire-place 6. v The mode of operation of the furnace is as follows: Supposing a steani boiler is to be fired, the igniting furnace is brought close to the boiler so that the tube 5 enters through the fireplace opening into the fireplace. The gasket 11 serves to secure a tight joint around the tube at the said openmg. started. The pulverous fuel and air are now introduced into the compartment 4 where. they are given a rotating movement by the screen '7 and thereby they are mixed. with one another and simultaneously heated from 35 the fireplace 6. The rotating movement contributes to holdthe particles suspended in the air. When the air ontaining pulverous fuel comes out of the compartment 4 it meets in the channel 10 with the flame place 6 and are burned or slide down into the fireplace. In the channel 10 the first ga'sifying of the fuel takes 'placebut the fuel must also be exposed to favorable igniting conditions for some moments. For this purpose the fuel is forced by pressure andl draft into the igniting tube 5, the walls of which will rapidly become red-hot by the action of the hot gases. Here an additional quantity of air is introduced through the tube 9. In the present case there is always plenty of air for the first ignition thereby enabling a high temperature to be obtained, which will promote further gasifying. For this purpose, however, an additional supply of air in the tube 5 is also required. As this quantity of air is introduced from the bottom tube 9 (by pressure or draft) it also The fireplace is fired and the fan is 80 contributes to hold the pulverous fuel suspended till the complete combustion has. taken 'lace. If one desires to obtain a very long ame the said quantity of air may be supplied at several points farther in in the fireplace.

The fireplace, however, has also another application. If the supply of pulverousl. fuel should at any time 'be'interrupted but the supply of air be not shut off the igniting compartment would be coole thus rendering a further ignition more diflicult. In the present case such cooling is prevented and the supply of fuel may be 1ncreased,

reduced or mterrupted. Thus the fireplace in several respects acts like a regulator without which the firing with ulverous fuel can never be executed practica lly to the greatest degree.

Having now described -my invention, what I claim as new and desire to secure by Letters Patent is:

1. In igniting furnaces for pulverous fuel, a portable box, a tube in the said box, forming the mixing compartment, means for introducing air and pulverous fuel into the said compartment, an i itin tube in the prolongation of the mixlng tu e and placed at some distance from the latter so as to form an intermediate spacebetween them,

and a fireplace located under the mixing tube, substantially as and for the purpose described.

2. In igniting furnaces for pulverous fuel, a box supported by wheels, a mixing tube in the said box, means for supplying air and pulverous fuel to the said mixln tube, means for causin the air and, pu verous fuel to rotate within the mixing tube, an

I .a 1 means for supplying air to the igniting tube,

igniting tube reaching some distance out of the box and laced in the prolongation of the mixing tu e and at some distance from the latter, so as to form an intermediate space between the tubes, means for supplying air to the i itin tube, a fireplace under the mixing tu an a firebridge between the fireplace and the igniting tube, substantially as described.

In witness whereof, I have hereunto signed my name in the presence of two subscribing witnes'ses.

NILSKARL HERMAN EKELUND. Witnesses:

G. Fmtmin, J. RASMUSSON. 

